1. Field of the Invention
The invention relates a pin standing resin (pin grid array) substrate, a method of making the same, pins, and a method of making the same, the pin being fabricated with a kovar (Fexe2x80x94Nixe2x80x94Co alloy) or a 42 alloy (Ni (42 wt %)xe2x80x94Fe alloy) serving as an input terminal and/or an output terminal thereon.
2. Description of the Related Art
A pin standing resin substrate has conventionally been known where pins as input and output terminals are stood on a resin substrate comprising a resin or a composite material containing a resin.
For example, FIG. 10 shows a partially enlarged cross sectional view of the pin standing resin substrate 201. The pin standing resin substrate 201 comprises a resin substrate 203 having a substantially rectangular and substantially plate-like (plated) shape and a lot of pins 221 stood thereon.
Of the two members, the resin substrate 203 has a resin insulating layer 205 formed with wired layers (not shown) inside or in a surface thereof, and many pin-pads 209 exposed from a solder resist layer 207 are formed on the main surface 203A (an upper portion in FIG. 10).
On the other hand, the pin 221 comprises the kovar, and comprises a rod like portion 221A of almost columnar shape and an enlarged diameter portion 221B of almost disk shape formed on the pin-pad 209. The pin 221 is fixed to the resin substrate 203 by connecting the whole enlarged diameter portion 221B and a part of the rod like portion 221A to the pin-pad 209 by means of a solder HD.
However, in such a pin standing resin substrate 201, in case the pin 221 receives a load, for example, when pulling the pin 221, the pin 221 (the rod like portion 221A) is not broken but, prior to this breaking, the resin substrate 203 (the pin-pad 209 and a lower portion thereof) is destroyed, and the solder-connected portion of the pin 221 and the pin-pad 209 might be destroyed.
In particular, for forming lots of inlet and outlet terminals on the resin substrates 203, it has been demanded to reduce pins in size and height. For example, in the pin standing resin substrate of reducing the diameter of the pin-pad 209 to be 0.9 to 1.1 mm, demands are that a total full length of the rod like portion and the enlarged diameter portion of the pin 221 is about 2 mm, a diameter of the rod like portion is about 0.3 mm, a diameter of the enlarged diameter portion is below 0.7 mm and a thickness thereof is under 0.2 mm. On the other hand, although such small sized pins are used, further demands are that bonding strength should be maintained high, for example, tensile strength at a 30 degree obliquity (tensile strength inclined 30 degrees) is to be 25.5 N (=2.60 kgf) or more, and further a minimum value is to be 22.2 N (=2.27 kgf) or more.
However, with respect to the pin standing resin substrates employing such small sized pins and pin-pads, although sizes are changed within ranges allowed in the above mentioned pins, requisite bonding strength (the tensile strength at the 30degree obliquity is 25.5 N or more in the average value, and 22.2 N or more in the minimum value) could not be satisfied.
The present invention has been realized in view of such circumstances, and it is an object of the invention to offer a pin standing resin substrate, the pin of which is less to be broken in case of receiving stress on pins, a method of making the same, pins to be used to the pin standing substrate, and a method of making the same.